110 likes | 254 Views
PhotoSlap. Hernisa Kacorri. A Multi-player Online Game for Semantic Annotation. what. http://photoslap.csie.org. why. Photo Metadata People: Who are in the picture? Objects: What objects are in the picture? Event: What was the event?. Time: When was the photo taken?
E N D
PhotoSlap Hernisa Kacorri A Multi-player Online Game for Semantic Annotation
what http://photoslap.csie.org
why • Photo Metadata • People: Who are in the picture? • Objects: What objects are in the picture? • Event: What was the event? • Time: When was the photo taken? • Location: Where was the picture taken? • manually annotating • Tedious and time-consuming • Need for incentives: • monetary rewards • promoting a common good • fun • automatic annotation • Embedded metadata in standard JPEG format (EXIF) • time • resolution • ISO • aperture • shutter speed • GPS-equipped devices • location
related work • Human Computation examples: • Label Me: web-based image annotation tool • Riya: visual search engine (combines manual labeling & machine learning) • ESP Game: interactive game in which a player attempts to label a given image presented by the system to match any label given by his online partner within a predefined time limit. • Automatic Image Annotation • requires: • Training the annotation system • Analyzing and transforming training images into feature vectors • Capturing relationships by probabilistic models:
game mechanism • Game Actions • Flip • Slap • Object • Trap • Scoring Mechanism • A player gets points : • – First to slap without drawing any objection. • – First to object without falling into a trap. • – Another player slaps on the trap he/she sets. • A player loses points: • – First to object and fall into the trap. • – No player slaps on the trap he/she sets.
game strategy analysis Subgame the expected payoff for player 3: Ptrap (- Strapped) + (1 - Ptrap) Sobject player 3 should object if: Ptrap < Sobject/ (Sobject + Strapped) The target strategy Game tree of the trap stage Game tree of the game stage
subgame perfect equilibrium depends on his/her belief about action of Player 1 depends on his/her belief about action of Player 2 Action of Player 3 depends on his/her belief about
gameplay • gameplay is allthe activities and strategies game designers employ to getand keep players engaged (Prensky 2002) that promote deep and persistent engagement. • The core elements of gameplay in PhotoSlap are: • Pattern-recognition challenge • Reaction time challenge • PhotoSlap is designed to be self-adaptive in that the competitors are carefully chosen so that the difficulty of challenges, the competitors’ reaction time, and their ability can be balanced to enable them to stay in the flow state. • The appearance of a matching pair is dynamicallyadjusted to follow a tension curve that has proper frequentpeaks [ p(t) = Ne ^(gt) ].
evaluation Is the game fun? PhotoSlap received an average score of 7.6 points on a 10-point scale. Is the game productive? productivity of the game: ismeasured by the links being built and the percentage of thecorrect links. each game can produce 12.3 links per minuteand 98.31% of them are correct. How good is the game strategy?
do you want more ? Paparas, D. 2008; Εγωιστική Απόθεση Φορτίου υπό συνθήκες Μερικής Γνώσης. Τμήμα Πληροφορικής και Τηλεπικοινωνιών ΕΚΠΑ von Ahn, L., and Dabbish, L. 2004; Labeling images witha computer game. In Proc. CHI ’04, 319–326. ACMPress. Ting-hsiang Huang Jane Yung-jen Hsu; Beyond Memories: Weaving Photos into Personal Social Networks